Disclaimer: I can't take credit for this Really Great Idea, I discovered it on Filth Wizardry. But it's too good not to pass on!
I had a bucket of Duplo blocks which my now nine-year-old grew out of a long time ago. I had them in my classroom but discovered that the kindergarten kids were much more interested in regular sized Lego blocks.
I had been considering donating them to a home day care or preschool but then came upon this Really Great Idea.
First I dumped the blocks into the sink and sanitized them using 1 Tbs of bleach per 1 gallon of water and let them soak for awhile, I rinsed them and spread them on a towel to air dry.
The drying part is pretty important before moving on to the next step.
I purchased Avery Removable Multi-Use Labels. Number 5418 works best, the labels are 1/2" x 3/4" and fit perfectly on the square Duplo bricks.
I used Sharpies to write lowercase letters on each label. I used a red Sharpie for vowels and blue for the consonants. Then applied each label to a Duplo block.
Letters should be placed horizontally so the Duplo "bumps" are facing to the left. The label on the Duplo block above is NOT placed correctly, but I only discovered that as I was typing this!
When the blocks are joined together, children can build words using the Duplos.
Then I labeled large Duplo blocks with Sight Words.
I love finding ideas like this...a new purpose for some old toys!